INFLUENCE OF HEPARIN COATING ON IN-VITRO BACTERIAL ADHERENCE TO POLY(VINYL CHLORIDE) SEGMENTS

End-point attached, covalently bound heparin has been shown to be effe ctive in preventing activation of the coagulation cascade by biomateri als. Data concerning its possible influence on bacterial attachment an d resistance to biomaterial-associated infection are, so far, lacking. In the present work, the in vitro adherence of Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coil, one isolate of each species, to plain poly(vinyl chloride) (plain PVC) and heparin coated poly(vinyl chloride) (EPA-PVC) segments was compared. Also, the influe nce of precoating the segments with human normal plasma for 2 h was st udied. S-35-Methionine was used to radiolabel bacteria. The segments w ere exposed to bacterial suspensions of approximately 10(7) colony for ming units (CFU) per milliliter at 37 degrees C for 0.5-6 h. Following repeated washing in phosphate buffered saline (PBS), radioactivity as sociated with the segments was measured. Plain PVC as compared to EPA- PVC bound significantly more cells of all three tested species. Plasma precoating significantly decreased adherence of the tested species to plain PVC but did not affect the binding to EPA-PVC. However, after p recoating with human plasma, EPA-PVC compared to plain PVC showed a hi gher binding of S. aureus which might possibly be due to bridging effe cts of fibronectin or other plasma proteins, interacting with S. aureu s.